Multiple definition of `main'

Hello
I just got the ZED2i on a fresh Ubuntu 20.04.
Than I go through the Tutorials of 3.6.0 and everything was fine, just the spaces in the folder name was not a good idea and run into errors.
Both camara samples, control and streaming are compiled fine.

BUT depth sensing, object detection and spatial mapping
got all the same Linker error.

[100%] Linking CXX executable ZED_Depth_Sensing
/usr/bin/ld: CMakeFiles/ZED_Depth_Sensing.dir/src/main.o: in function main': main.cpp:(.text.startup+0x330): multiple definition of main’; CMakeFiles/ZED_Depth_Sensing.dir/CMakeFiles/3.16.3/CompilerIdCXX/CMakeCXXCompilerId.o:CMakeCXXCompilerId.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status
make[2]: *** [CMakeFiles/ZED_Depth_Sensing.dir/build.make:124: ZED_Depth_Sensing] Error 1
make[1]: *** [CMakeFiles/Makefile2:76: CMakeFiles/ZED_Depth_Sensing.dir/all] Error 2
make: *** [Makefile:84: all] Error 2

multiple definition of `main’
I’m searching for a second function main(), but I didn’t find that.

Can anybody help me out of this error?

Best

Volker

Seens like me is the only one how got this error on two different computers.
Never mind.